(1) Field of the Invention
The present invention relates to a printed matter, a printing apparatus, and a printing precision measuring method, the printed matter being printed with the printing apparatus such as an inkjet printing apparatus.
(2) Description of the Related Art
The apparatus of this type conventionally includes a first apply section, a first detection signal generating section, a second apply section, a second detection signal generating section, and a determining section. See, for example, Japanese Patent Publication No. 2006-327072A.
The both-side printing apparatus includes the first apply section configured to apply information on first detection signal generation to a front surface of a printing sheet. The information allows identifying a page. The first detection signal generating section reads out the information on first detection signal generation to generate a first detection signal. The second apply section applies information on second detection signal generation to a rear face of the printing sheet. The information allows identifying a page. The second detection signal generating section reads out the information on second detection signal generation to generate a second detection signal. The determining section determines a condition of both-side printing in accordance with the first and second detection signals.
With the both-side printing apparatus, the determining section determines the condition of both-side printing. This ensures to perform convenient inspection in the both-side printing.
The both-side printing apparatus mentioned above includes additional elements, such as the first detection signal generating section, the second detection signal generating section, and the determining section. These additional elements do not directly contribute to printing itself. Consequently, convenient inspection can be ensured in the both-side printing.
On the other hand, an apparatus having no additional element as above for inspection such as an inkjet printing apparatus of line scan head type determines precision of the printed matter by a user manually as under upon delivering the printing apparatus.
With the both-side printing, a surface of the printing sheet is not visible from a rear face thereof or vice versa. Accordingly, a user firstly performs printing of register marks with the same position and dimension to the surface and the rear face of the printing sheet. Secondary, a hole is bored into the center of one of the printed register marks for pagination in the printing sheet with a pushpin, for example, from one side thereof. When the hole in the center of the register mark for pagination on one side is in the same position as that on the other side, it means that no problem occurs in printing precision. On the other hand, when the hole in the center of the register mark for pagination on one side is different in position from that on the other side, it means necessity for adjustment of printing heads. Here, the both-side printing precision translates into shearing/folding precision in a process subsequent to the printing process.
Consequently, poor precision leads to poor printing. Thus, the both-side printing precision is an important point for assuring the printed matter. In transaction printing in which different contents are printed to every sheet, both-side printing precision typically ranges from 0.2 to 0.5 mm. In printing applicable to coated paper, both-side printing precision typically ranges from 0.1 to 0.2 mm.
Besides the above method, a method exist in which a printed printing sheet is placed on a light table with an intense light source to see a register mark for pagination on the opposite side through the printing sheet, thereby determining printing precision.
However, the examples of the conventional apparatus with such constructions have the following problems.
The conventional apparatus needs to include the additional elements, causing increased cost to the apparatus. Such a problem may arise. In addition, the conventional manually-inspecting method with the pushpin also depends on positional precision of a hole bored by a user with the pushpin. Accordingly, it would be hard to use the method as a measuring method having a precondition of adjusting an apparatus. Moreover, the conventional inspecting method using the light table may cause possibility of not performing inspection depending on a thickness of the printing sheet.